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<div><a href="../../index.html">Home</a> &gt;  <a href="../index.html">matgraph</a> &gt; <a href="index.html">@partition</a> &gt; merge.m</div>

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<h1>merge
</h1>

<h2><a name="_name"></a>PURPOSE <a href="#_top"><img alt="^" border="0" src="../../up.png"></a></h2>
<div class="box"><strong>merge(p,x,y) --- form a partition from p by combining x and y's parts.</strong></div>

<h2><a name="_synopsis"></a>SYNOPSIS <a href="#_top"><img alt="^" border="0" src="../../up.png"></a></h2>
<div class="box"><strong>function q = merge(p,x,y) </strong></div>

<h2><a name="_description"></a>DESCRIPTION <a href="#_top"><img alt="^" border="0" src="../../up.png"></a></h2>
<div class="fragment"><pre class="comment"> merge(p,x,y) --- form a partition from p by combining x and y's parts.
 If x or y are out of range, p is returned.</pre></div>

<!-- crossreference -->
<h2><a name="_cross"></a>CROSS-REFERENCE INFORMATION <a href="#_top"><img alt="^" border="0" src="../../up.png"></a></h2>
This function calls:
<ul style="list-style-image:url(../../matlabicon.gif)">
<li><a href="np.html" class="code" title="function m = np(p)">np</a>	np(p) --- number of parts in the partition p</li><li><a href="nv.html" class="code" title="function n = nv(p)">nv</a>	nv(p) --- number of vertices (elements) of a partition</li></ul>
This function is called by:
<ul style="list-style-image:url(../../matlabicon.gif)">
<li><a href="plus.html" class="code" title="function r = plus(p,q)">plus</a>	plus --- p+q is the join of p and q</li></ul>
<!-- crossreference -->


<h2><a name="_source"></a>SOURCE CODE <a href="#_top"><img alt="^" border="0" src="../../up.png"></a></h2>
<div class="fragment"><pre>0001 <a name="_sub0" href="#_subfunctions" class="code">function q = merge(p,x,y)</a>
0002 <span class="comment">% merge(p,x,y) --- form a partition from p by combining x and y's parts.</span>
0003 <span class="comment">% If x or y are out of range, p is returned.</span>
0004 
0005 q = p;
0006 n = <a href="nv.html" class="code" title="function n = nv(p)">nv</a>(p);
0007 
0008 <span class="keyword">if</span> (x&lt;1) || (x&gt;n) || (y&lt;1) || (y&gt;n) || (x==y)
0009     <span class="keyword">return</span>
0010 <span class="keyword">end</span>
0011 
0012 rx = find(p.array(:,x));
0013 ry = find(p.array(:,y));
0014 
0015 <span class="keyword">if</span> rx == ry
0016     <span class="keyword">return</span>
0017 <span class="keyword">end</span>
0018 
0019 <span class="comment">% merge row ry into row rx</span>
0020 q.array(rx,:) = q.array(rx,:) | q.array(ry,:);
0021 
0022 <span class="comment">% remove row ry</span>
0023 
0024 idx = [1:ry-1,ry+1:<a href="np.html" class="code" title="function m = np(p)">np</a>(p)];
0025 q.array = q.array(idx,:);
0026 q.array = sortrows(q.array);</pre></div>
<hr><address>Generated on Fri 30-Apr-2010 07:51:16 by <strong><a href="http://www.artefact.tk/software/matlab/m2html/">m2html</a></strong> &copy; 2003</address>
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